Each die of a semiconductor wafer typically is tested to determine if the operational characteristics for the die are within specified limits. Conventional tests apply a Single Threshold Test Limit (STL) to test each die. The STL is a single fixed threshold for the semiconductor wafer for a measured parameter. Accordingly, If a measured parameter for a die exceeds the STL, this indicates that the die will not operate according to specifications and the die is typically disqualified for operation and discarded. However, because of process variations in the formation of the wafer, some failed dies will not be detected through application of an STL test. Accordingly, an improved technique for detecting failed dies would be advantageous.